Semiconductor package having routing traces therein

ABSTRACT

A method of and device for making a semiconductor package. The method comprises etching a first side of a metallic piece forming a leadframe with one or more wire bonding pads, applying a first protective layer on the first side, etching a second side of the metallic piece forming one or more conductive terminals, and applying a second protective layer on the second side. The semiconductor package comprises wire bonding pads in pillars structure surrounding a die attached to the leadframe. One or more terminals are on the bottom side of the semiconductor package.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority under 35 U.S.C. §119(e) of the U.S.Provisional Patent Application Ser. No. 62/043,276, filed Aug. 28, 2014and titled, “A Semiconductor Package Having Routing Traces Therein,”which is also hereby incorporated by reference in its entirety for allpurposes.

FIELD OF THE INVENTION

The present invention relates to the field of semiconductor. Morespecifically, the present invention relates to a semiconductor packageand its manufacturing methods.

BACKGROUND OF THE INVENTION

Conventional QFN (Quad Flat No-Lead) package contains traces that areexposed from the bottom of the package. The traces are vulnerable tocontamination as well as mechanical damage. The contamination can causean electrical short circuit between adjacent leads. The mechanicaldamages can cause open circuit. Further, the thickness of theconventional QFN package should be reduced to meet the needs of modernelectronic devices.

SUMMARY OF THE INVENTION

A semiconductor package is disclosed which includes internal routingtraces therein and a method of making the same. The features/advances ofthe semiconductor packages and the method of making them includereducing thickness of the electronic devices, having routable traces ina lead frame, and providing a protection layer to the traces.

Using the semiconductor package construction or the method of making itdisclosed herein, the size of the electronic products incorporating suchpackages (such as a cell phone, PDA, and laptop) is minimized. In someembodiments, the semiconductor package comprises a lead frame, whichreplaces a typical laminate substrate that has a plurality of metallicrouting layers. In some embodiments, the lead frame includes routingtraces between the point of the electric connection to the IC chip andthe point of the electric connection to external components, such as amother board. In some embodiments, the semiconductor package provides aprotection layer to the traces, which prevents the contamination of thetraces from the environment.

In a aspect, a method of making a semiconductor package comprisesetching a first side of a metallic piece to form a leadframe with one ormore wire bonding pads, applying a first protective layer on the firstside, etching a second side of the metallic piece to form one or moreconductive terminals, and applying a second protective layer on thesecond side.

In some embodiments, the one or more wire bonding pads comprise a pillarstructure. In other embodiments, the one or more wire bonding pads arein a position higher than a position of a die attached to the leadframe.In some other embodiments, the one or more wire bonding pads form acavity allowing a die to fit within the cavity. In some embodiments, theone or more conductive terminals are beneath a die attached to theleadframe. In other embodiments, none of the one or more conductiveterminals are beneath a die attached to the leadframe. In some otherembodiments, the leadframe comprises an electric conductive path fromthe one or more wire bonding pads to the one or more conductiveterminals. In some embodiments, the method further comprises aconductive trace between the one or more wire bonding pads and the oneor more conductive terminals. In other embodiments, the method furthercomprises coupling a die to the leadframe. In some other embodiments,the method further comprises filling a cavity beneath a die attached tothe leadframe. In some embodiments, the method further comprises platingon the one or more wire bonding pads.

In another aspect, a semiconductor package comprises a first pillarstructure on the first end of a leadframe, a second pillar structure onthe second end of the lead frame, a cavity between the first and thesecond pillars, and a die physically coupling with the leadframe withinthe cavity. In some embodiments, the pillars are taller than the die. Inother embodiments, a first molding material encapsulating a side wall ofthe first pillar, a side wall the second pillars, and the die. In someother embodiments, the first pillar couples with a first wire bondingpad. In some embodiments, the leadframe couples with a second wirebonding pad.

In another aspect, a method of forming a semiconductor package comprisesetching a metallic piece forming a shaped leadframe, applying a maskwith a predetermined thickness on the leadframe to a first predeterminedarea on the shaped leadframe, such that one or more apertures with apredetermined depth are formed, and depositing a conductive material tothe aperture.

In some embodiments, the conductive material forms a pillar structure.In other embodiments, the pillar structure has a height close to thethickness of the mask. In some other embodiments, the depositingcomprises plating.

In another aspect, a method of testing a semiconductor packagecomprising electrically coupling a first semiconductor package with asecond semiconductor package, wherein the second semiconductor packagecomprises a protective layer encapsulating the entire secondsemiconductor package except at least two contacting points on one sideand one or more contacting points on the opposite side and sending anelectrical signal from the second semiconductor package to the firstsemiconductor package. In some other embodiments, the testeesemiconductor package comprises a BGA, QFN, or a WLCSP package.

Other features and advantages of the present invention will becomeapparent after reviewing the detailed description of the embodiments setforth below.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described by way of examples, with reference tothe accompanying drawings which are meant to be exemplary and notlimiting. For all figures mentioned herein, like numbered elements referto like elements throughout.

FIG. 1 illustrates a semiconductor package structure 100 in accordancewith some embodiments of the present invention.

FIG. 2 illustrates another semiconductor package structure 200 inaccordance with some embodiments of the present invention.

FIG. 3 illustrates another semiconductor package structure 300 inaccordance with some embodiments of the present invention.

FIGS. 4A-4G illustrate a semiconductor package making method 400 inaccordance with some embodiments of the present invention.

FIG. 5 illustrates a double protective layer structure manufacturingmethod 500 in accordance with some embodiments of the present invention.

FIG. 6 illustrates a reserved die cavity premolded structuremanufacturing method 600 in accordance with some embodiments of thepresent invention.

FIGS. 7A-7F are cross sectional views illustrating die embeddedstructures 700 in accordance with some embodiments of the presentinvention.

FIG. 8 illustrate another leadframe with embedded die making method 800in accordance with some embodiments of the present invention.

FIG. 9 illustrate a pillar forming method 900 in accordance with someembodiments of the present invention.

FIG. 10 is a flow chart illustrating a semiconductor packagemanufacturing method 1000 in accordance with some embodiments of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Reference is made in detail to the embodiments of the present invention,examples of which are illustrated in the accompanying drawings. Whilethe invention is described in conjunction with the embodiments below, itis understood that they are not intended to limit the invention to theseembodiments and examples. On the contrary, the invention is intended tocover alternatives, modifications and equivalents, which can be includedwithin the spirit and scope of the invention as defined by the appendedclaims. Furthermore, in the following detailed description of thepresent invention, numerous specific details are set forth in order tomore fully illustrate the present invention. However, it is apparent toone of ordinary skill in the prior art having the benefit of thisdisclosure that the present invention can be practiced without thesespecific details. In other instances, well-known methods and procedures,components and processes have not been described in detail so as not tounnecessarily obscure aspects of the present invention. It is, ofcourse, appreciated that in the development of any such actualimplementation, numerous implementation-specific decisions must be madein order to achieve the developer's specific goals, such as compliancewith application and business related constraints, and that thesespecific goals vary from one implementation to another and from onedeveloper to another. Moreover, it is appreciated that such adevelopment effort can be complex and time-consuming, but isnevertheless a routine undertaking of engineering for those of ordinaryskill in the art having the benefit of this disclosure.

FIG. 1 illustrates a semiconductor package structure 100 in accordancewith some embodiments of the present invention. The structure 100comprises a cavity 102 formed between wire bond pads 104. A person ofordinary skill in the art appreciates that there can be any number ofwire bond pads, according to the requirements of an integrated circuitchip intended to be coupled to the package. In some embodiments, thecavity 102 comprises a space allowing one or more IC chips to be fittherewithin. In some embodiments, a die 106 is placed inside the cavity102 in a way that a bottom surface 106A of the die 106 is lower than thetop surface 104A of the wire bond pads 104. One or more traces 108 eachprovides an electrical conductive/signal pathway 108A from a wire bondpad 104 to a terminal 110. In some embodiments, the terminal 110comprises a lateral displacement from the wire bond pad 104, which makesthe terminal 110 not directly located beneath the wire bond pads 104. Insome embodiments, a plating layer 124 is plated/coated/spread on a wirebonding pad 104, such that a wire 116 is able to couple the platinglayer 124 with the IC chip 114.

In some embodiments, a protective layer 112 encloses/coverssubstantially all or a predetermined portion of the bottom of thepackage, such that the traces 108/terminals 110 areisolated/insulated/protected from contamination from the environment. Insome embodiments, the protective layer 112 is made using a moldedunderfill (MUF) material through using a molding process.

In some embodiments, an IC 114 having the die 106 is coupledwith/attached to the leadframe 116 by a die attaching film (DAF) 118. Insome embodiments, a gap 120 is formed between the DAF 118 and theprotective layer 112. The gap 120 can be filled by a molding compound122 using a molding process.

FIG. 2 illustrates another semiconductor package structure 200 inaccordance with some embodiments of the present invention. Thesemiconductor package structure 200 is similar to the semiconductorpackage structure 100 of FIG. 1 in most parts. Accordingly, descriptionsto similar structures in the package structure 100 are also applicablehere. The IC chip 208 is attached to the leadframe 210 and the traces206 via an adhesive 212, such as epoxy or epoxy based adhesive. Theadhesive 212 can be a deformable adhesive. As shown in the view 202A, aportion 214 of the adhesive 212 is flowing to fill the gap 204 forming acompleted filled area 202 in a die attaching process. A person ofordinary skill in the art appreciates that the deformation/gap fillingprocess can be triggered/performed by applying a pre-determinedtemperature or any other methods during or subsequent to the dieattaching process.

FIG. 3 illustrates another semiconductor package structure 300 inaccordance with some embodiments of the present invention. Thesemiconductor package structure 300 is similar to the semiconductorpackage structure 100 of FIG. 1 in most parts. Accordingly, descriptionsto similar structures in the semiconductor package structure 100 arealso applicable here. An IC 310 is attached/coupled to a die attachedpad (DAP) 302 on a lead frame 312 via an adhesive 304. One or moreterminals 306 are located beneath the DAP. The terminals 306 are used toprovide ground signal to the DAP. In some embodiments, the terminalsdissipate an amount of heat from the IC chip 310. In some embodiments,the sides of traces 314 are exposed. In some other embodiments, thetraces 316 are enclosed/covered and not exposed. In some embodiments,the terminals 303 are below the traces 316.

FIGS. 4A-4G illustrate a semiconductor package making method 400 inaccordance with some embodiments of the present invention. At a Step 401(FIG. 4A), a metallic foil 402 is provided. In some other embodiments,an entire body or a predetermined portion of the metallic foil 402comprises copper, copper alloy, iron-nickel alloy, or a combinationthereof. In some embodiments, the thickness of the metallic foil rangesfrom 10-300 micron. For example, the thickness of the metallic foil is150 micron.

At a Step 403 (FIG. 4B), a first mask 404 is placed over a top surfaceof the foil 402. In some embodiments, the first mask 404 is a mechanicalmask. In some other embodiments, the first mask 404 are aphoto-sensitive mask. In some other embodiments, the first mask 404defines the position of the wire bond pads 410 and routing traces 408.The areas that are not covered by the first mask 404 is removed/etchedforming a first etched area 406. For example, the view 412 shows anexample of a top surface view of a metallic foil. An area 414 that iscovered by a mask is the area that is not etched; whereas, the areasthat are not covered by the mask form an etched area 416. The etchingprocess can be performed using a chemical etching solution that reactswith the metal, such that the metal is etched.

At a Step 405 (FIG. 4C), a second mask 420 is applied over the topsurface of the wire bonding pads 410. In some embodiments, the secondmask 420 is a mechanical mask. In some other embodiments, the secondmask 420 is a photo-sensitive mask or a hard mask. In some embodiments,a plating layer of wire bonding metallic material is formed on the wirebonding pad as the second mask 420, such that the plating layer alsoserves as the second mask 420 in a second etching process. In someembodiments, the area exposed and not covered by the second mask 420 isremoved/etched, such as the second etched areas 418 are formed. The areathat is covered by the second mask 420 is not being removed. As a resultof the first etching process in the Step 403 and the second etchingprocess in the Step 405, a first plane, in which the top surfaces ofwire bond pads are located, a second plane, in which the top surfaces ofthe traces are located, and a third plane, in which the bottom surfaceof the first protective layer is located, are formed. A person ofordinary skill in the art appreciates that the sequences of forming theplating layer and the etching processes can be performed in any suitableorders, including a process performed in the following sequence: (1)forming a plating layer, (2) forming a 1^(st) etching mask, (3)performing a 1^(st) etching, and (4) performing a 2^(nd) etching byusing the plating layer as an etching mask.

At a Step 407 (FIG. 4D), an IC chip 424 is attached to a leadframe 422,which was previously manufactured through the Steps 401-405. In someembodiments, a flip chip can be attached to the wire bond pad 420 bysolder balls/bumps. In some embodiments, the space 426, beneath the ICchip 422, is completely filled. The flat bottom surface of the leadframe422 provides a firm support to the bonding sites, which eliminates thebouncing effect during bonding process. In some embodiments, a flip chipis included. The substantial co-planarity of the contact pads is ensuredby having an uniform thickness of the leadframe, which minimizes thenon-contact failure during a flip chip attachment.

At a Step 409 (FIG. 4E), a mold compound 428 is used to encapsulate theIC 424 and the bonding wires 430. A portion of the leadframe 422 is alsocovered by the molding compound 428. The molding compound 428 can be anymolding material, such as polymers (i.e., polyurethane, polyethylene,polypropylene, and silicones). In some embodiments, the molding processcan be performed by using a transfer molding.

At a Step 411 (FIG. 4F), lead frame 422 is etched from the bottomsurface. A predetermined portion 432 of the leadframe 422 is etched awayto form one or more terminals 434. In some embodiments, a plating layeris disposed at a bottom surface of the leadframe at predeterminedlocations (such as the locations of the terminals 434) as etching mask,such that the etching occurs at the areas without mask and not at theareas with the mask. After the leadframe 422 is etched from the bottomsurface, the bottom surface of the mold compound 428 is exposed from theleadframe 422 and the traces are electrically isolated from each other.In some embodiments where the die attach pad is provided, the traces areelectrically isolated from the die attach pad after the etching from thebottom surface of the leadframe. In some embodiments, the terminals 434are underneath the IC 424. In some other embodiments, the terminals 434are not underneath the IC 424, such as terminal 436. A person ofordinary skill in the art appreciates that the terminals can be locatedat any predetermined locations and/or directions. In some embodiments,the terminals 436 provide a stand-off height from the surface on whichthe package is mounted.

At Step 413 (FIG. 4G), a protective layer 438 is formed at the bottom ofthe leadframe 422. The protective layer 438 encloses the entireside/substantial all of the entire side of the terminals 434 and 436while leaving the bottom surfaces 434A and 436A uncovered, such that theterminals 434 and 436 conducts/passes electric signals/electricity. Insome embodiments, the bottom surfaces 434A and 436A of the terminals 434and 436 are covered by another conductive protective layers. In someembodiments, the protective layers are made by a molding process. Insome other embodiments, the protective layer comprises a moldingunderfill (MUF), wherein the filler size of the MUF is smaller than thatof the mold compound 428.

FIG. 5 illustrates a double protective layer structure manufacturingmethod 500 in accordance with some embodiments of the present invention.At a Step 501, an etched leadframe 504 is formed with a predeterminedshaped/contour. The etched leadframe 504 is able to be made by etching ametallic foil as a first etching process, which is a process similar tothe Steps 401-405 of the method 400 above. A first protective layer 506is applied on top of the leadframe 504 prior to a die assemble process,such that a leadframe 502 having a first protective layer 506 on top isformed. At a Step 503, one or more terminals 508 are formed on thebottom side of the leadframe 502 by a second etching process. Once thesecond etching process is done, a second protective layer 510 is appliedto enclose the side of the terminals 508 and covers substantial all orall of the bottom surfaces of the leadframe formed by the second etchingprocess. With the process described above, a double protective layerstructure 512 is formed. A person of ordinary skill in the artappreciates that the sequences of forming the first and secondprotective layers and etching processes can be performed in any orders.

The double protective layer structure 512 comprises a plating layer 518on the wire bonding pads exposed from the top surface of the firstprotective layer 506 and the terminals 508 exposed from the bottomsurface of the second protective layer 510. The traces 520 are embeddedinside the first and second protective layers 506 and 510.

At a Step 505, a die 514 is attached to the top side of the doubleprotective layer structure 512. Wires 516 are bonded to the platinglayer 518 on the wire bonding pads forming a conductive/signal path fromthe die 514, wire bonds 516, wire bond pads 518, traces 520, to theterminals 508. At a Step 507, a routing layer 522 is plated/added ontothe terminals 508. It is an optional process to plate/add the routinglayer 522 on the terminals 508 during the leadframe fabrication stageand before the die attach process. The benefit is that the leadframe canbe fabricated at one location and package assembly processes can be donein a separate location.

FIG. 6 illustrates a reserved die cavity premolded structuremanufacturing method 600 in accordance with some embodiments of thepresent invention.

At a Step 603, a first protective layer 610 is applied on top surface ofthe leadframe 602 leaving a reserved cavity 612. The cavity 612 can bereserved for coupling a die 614. A second protective layer 608 isapplied on the bottom of the leadframe 602.

At a Step 605, a die 614 is coupled with the leadframe 602 and isattached inside the cavity 612 with wires bonded with the wire bondingpads. A molding material 616 is molded over the cavity and encloses theentire top surface of the leadframe 602 with the die 614.

As shown in view 618, wire bonding pads 620 can be coupled with thetraces 622 in some embodiments forming a double layered wire bonding padstructure. In this case, a portion of the traces or a portion body ofthe leadframe 602 are exposed for coupling with the wire bonding pads. Aperson of ordinary skill in the art appreciates that any numbers of wirebonding pads can be coupled with the leadframe 602.

FIGS. 7A-7F are cross sectional views illustrating die embeddedstructures 700 in accordance with some embodiments of the presentinvention. The die embedded structures provides advantageous features.The structure 701 (FIG. 7A) comprises one or more pillars 708 forming aprotective structure protecting the die 702, wires 704, and the wirebonding pads 706 to prevent damages causing by outside forces. In theexample having two or more pillars 708 as shown, the pillars 708 areformed around the die 702 forming a cavity 712 having the die 702, wires704, and wire bonding pads 706 therewithin.

The view 701A (FIG. 7B) is top view of the structure 701, which showsthat four pillars 708 are located at four corners surrounding the die702. Other locations are also possible. A person of ordinary skill inthe art appreciates that any number of pillars are within the scope ofthe present invention. In some embodiments, the pillars are in acontinuous structure. For example, the pillars can be a wall structuresor a bowl structure surrounding the die 702.

The structure 703 (FIG. 7C) shows an exemplary double die in a doublelayered structure. A first layer 728 with a die enclosed in a leadframecouples with a second layer 730. The coupling of a first die 720 and thesecond die 722 is done by coupling the second die 722 via the wire bonds724 in the second layer 730 with the wire bonding pads and pillars 726through traces 732, wire bonding pads 734, and wires 736 with the firstdie 720 in the first layer 728.

The structure 705 (FIG. 7D) shows an example of a tested package 705 onthe die embedded leadframe structure. The tested package 705electrically couples with the die embedded structure 744. An electricalsignal is received at the tested package 705 sending from the dieembedded structure 744 through the solder bump 742. In some embodiments,a complete packages, such as BGA (ball grid array), QFN (Quad FlatNo-leads package), WLCSP (wafer-level chip-scale package) can beelectrically and functionally tested prior attaching to a moldedleadframe. A person of ordinary skill in the art appreciates that a flipchip can be used to replace the IC/die disclosed throughout the presentspecification.

The structure 707 (FIG. 7E) shows an exemplary double die in a separateddouble layered structure. The bottom layer of a leadframe structure 750can be made using the method 600 of FIG. 6. The leadframe structure 750can be separated by an insulation layer 754 with the second electroniclayer 752. The die 758 electronically couples with the die 760 viarouting traces 756. A portion of the routing traces 756 are in theinsulation layer 754 forming conducting paths. In some embodiments, theinsulation layer 754 serves as an adhesion for coupling the leadframestructure 750 and the second electronic layer 752.

The structure 709 (FIG. 7F) shows an exemplary die attach paddle (DAP)770 included in the leadframe. The bottom surface of the DAP is exposedfrom the bottom surface of the protective layer 774. In someembodiments, one or more terminals are formed at the DAP using apressure cutting/pressing process or an etching process described above.

FIG. 8 illustrates another leadframe with embedded die making method 800in accordance with some embodiments of the present invention. At a Step801, a shaped leadframe 802 is formed having one or more pillars 808having a height greater than the thickness of a IC chip/die 804embedded. A first set of wire bonding pads 810 are on top of the pillars808. The leadframe 802 can be formed using the Steps 401-405 of the FIG.4 above. A die 804 is attached and bonded with the second wire bondingpads 806.

At a Step 803, a first protective layer 812 is applied on the leadframe802 covering/encapsulating the die 804, wires, and the second wirebonding pads 806. The first wire bonding pads 810 are exposed forfurther uses, such as connecting with another electronic components(e.g., another IC chip). The first protective layer 812 can be a moldedunderfill material.

At a Step 805, an etching process is performed. The bottom surface ofthe leadframe 802 is etched forming one or more terminals 814. Theterminals of the present invention can be in any shape, such as arounded pillar structure. At a Step 807, a second protective layer 816is applied on the leadframe 802 enclosing the entire side/substantiallythe entire side of the one or more terminals 814.

FIG. 9 illustrates a pillar forming method 900 in accordance with someembodiments of the present invention. At a Step 901, a metallic foil 902is provided. In some other embodiments, an entire body or apredetermined portion of the metallic foil 902 comprises copper, copperalloy, iron-nickel alloy, or a combination thereof. In some embodiments,the thickness of the metallic foil ranges from 10-300 micron. Forexample, the thickness of the metallic foil is 150 micron.

At a Step 903, a first mask 904 is applied over a top surface of thefoil 902. In some embodiments, the first mask 904 is a mechanical mask.In some other embodiments, the first mask 904 is a photo-sensitive mask.The area that are not covered by the first mask 904 is removed/etchedforming a first etched area 906.

At a Step 905, a plating mask 908 is applied on the etched leadframe902. One or more openings 910 are formed (e.g., drilled)/reserved on theplating mask (a plating layer). The locations of the openingscorresponds to the locations where pillars will be formed subsequently.The view 905A is a top view of the etched leadframe 902 with the appliedplating mask 908.

At a Step 907, one or more pillars 912 and wire bond pads 914 are formedby plating, such as an electronic plating process. The pillars 912 areformed on the location of the opening 910. The wire bond pads 914 areformed on top of the pillars 912. The leadframe 902 can function as aconductor providing an electrical conductive path/plating current pathduring the plating processes. The method 900 is able to manufacturepillars with any predetermined height, which can be determined by thethickness of the plating mask 908. For example, the pillar 912 can behigher, shorter, or equal to the thickness of die attached to theleadframe. Any predetermined surface areas of the pillars are within thescope of the present invention, such as 1 mm or greater than 1 nm.

FIG. 10 is a flow chart illustrating a semiconductor packagemanufacturing method 1000 in accordance with some embodiments of thepresent invention. At a Step 1002, a predetermined shape of leadframe isformed by using an etching process. At a Step 1004, one or more wirebond pads are formed. At a Step 1006, a die is attached to theleadframe. In some embodiments, the leadframe comprises a cavityconfigured for fitting the die, such as snug-fit. At a Step 1008, afirst protective layer is applied on the top surface of the leadframe.At a Step 1010, one or more terminals are formed by etching on thebottom surface of the leadframe. At a Step 1012, a second protectivelayer is applied on the bottom surface of the leadframe. The method 1000can stop at a Step 1014. A person of ordinary skill in the artappreciates that a flip chip can be used to replace the IC/die disclosedthroughout the present specification. The steps described in the abovemethods/processes can be performed in any sequences/orders. For example,the bottom side terminals can be formed before the etching of the topside features of the leadframe.

To utilize the semiconductor package, the leadframe based structure isapplied in any manner appropriate such as incorporated in a BGA, QFN,and WLCSP packages. The leadframe based structure is used in the samemanner that other electronic components are used, for example, makingelectronic and/signal coupling among IC chips. In production, theleadframe based structure is able to be generated using theimplementations described.

In operation, the leadframe based structure serves as the base of thesemiconductor package, which generates significant social, economic andenvironmental benefits. By having the leadframe based structure, thedies and wires are better shielded and protected.

The present invention has been described in terms of specificembodiments incorporating details to facilitate the understanding ofprinciples of construction and operation of the invention. Suchreference herein to specific embodiments and details thereof is notintended to limit the scope of the claims appended hereto. It is readilyapparent to one skilled in the art that other various modifications canbe made in the embodiment chosen for illustration without departing fromthe spirit and scope of the invention as defined by the claims.

What is claimed is:
 1. A method of making a semiconductor packagecomprising: a) etching a first side of a metallic piece forming aleadframe with one or more pads; b) applying a first protective layer onthe first side; c) etching a second side of the metallic piece formingone or more conductive terminals; and c) applying a second protectivelayer on the second side.
 2. The method of claim 1, wherein the one ormore pads comprise a pillar structure.
 3. The method of claim 1, whereinthe one or more pads are in a position higher than a position of a dieattached to the leadframe.
 4. The method of claim 1, wherein the one ormore pads forms a cavity allowing a die to fit within the cavity.
 5. Themethod of claim 1, wherein the one or more conductive terminals arebeneath a die attached to the leadframe.
 6. The method of claim 1,wherein none of the one or more conductive terminals are beneath a dieattached to the leadframe.
 7. The method of claim 1, wherein theleadframe comprises an electric conductive path from the one or morepads to the one or more conductive terminals.
 8. The method of claim 1,further comprising a conductive trace between the one or more pads andthe one or more conductive terminals.
 9. The method of claim 1, furthercomprising coupling a die to the leadframe.
 10. The method of claim 1,further comprising filling a cavity beneath a die attached to theleadframe.
 11. The method of claim 1, further comprising plating on theone or more pads.
 12. A semiconductor package comprising: a) a firstpillar structure on the first end of a leadframe; b) a second pillarstructure on the second end of the lead frame; c) a cavity between thefirst and the second pillars; and d) a die physically coupling with theleadframe within the cavity.
 13. The semiconductor package of claim 12,wherein the pillars are taller than the die.
 14. The semiconductorpackage of claim 12, further comprising a first molding materialencapsulating a side wall of the first pillar, a side wall the secondpillars, and the die.
 15. The semiconductor package of claim 12, whereinthe first pillar couples with a first wire bonding pad.
 16. Thesemiconductor package of claim 15, wherein the leadframe couples with asecond wire bonding pad.
 17. A method of forming a semiconductor packagecomprising: a) etching a metallic piece forming a shaped leadframe; b)applying a mask with a predetermined thickness on the leadframe to afirst predetermined area on the shaped leadframe, such that one or moreapertures with a predetermined depth are formed; and c) depositing aconductive material to the aperture.
 18. The method of claim 17, whereinthe conductive material forms a pillar structure.
 19. The method ofclaim 18, wherein the pillar structure has a height close to thethickness of the mask.
 20. The method of claim 17, wherein thedepositing comprises plating.
 21. A method of testing a semiconductorpackage comprising: a) electrically coupling a first semiconductorpackage with a second semiconductor package, wherein the secondsemiconductor package comprises a protective layer encapsulating theentire second semiconductor package except at least two contactingpoints on one side and one or more contacting points on the oppositeside; and b) sending an electrical signal from the second semiconductorpackage to the first semiconductor package.
 22. The method of claim 21,wherein the first semiconductor package comprises a BGA, QFN, or a WLCSPpackage.